If you've been following my little driveshaft out of round / vibration issue, then here is an update.

On Monday, I ordered a brand new 3.5" alum driveshaft and new 1350 slip yoke. Solid Dana Spicer u-joints (1350 front and 1330 big cap in the rear).

I get the shaft in the mail yesterday. Can't believe how light it is. So I mic the joints to make sure all is well and it is. I also mic the slip yoke vs my old (and only one I own) slip yoke. Looks like my old one was getting worn out due to the out of round steel driveshaft and old age.

Anyways, It all goes in nice and I go for a ride.

MY GOD!!!! It's like a brand new freaking car. Not a single noise / vibration / squeak or anything. Had it up to around 90 and smooth as silk. Threw it in neutral at around 60mph and I had to look at the tach to make sure the car didn't shut off. It was so super quiet that I didn't know what to do. It was like riding a bike down a hill. Not a noise to be heard. Shifting into gears was even easier.

I think I've found my vibration problem from the past 8 years. Don't get a driveshaft built by DriveLine Services in Pittsburgh. They built the old one and had them check it / shorten it at times / re-balance and re-check it a ton of times. They don't know what they are doing.

I got this new one from DynoTech in Michigan. So far, great quality and my problem(s) seem solved!!!!!

I gotta wonder how much the slip yoke wear contributed to the problem. If you are seeing wear on the outside than the inside which is even more critical is probably worse.

I don't know the specifics of your vibration problem but I encountered a problem with a slip yoke that looked ok but had worn splines from years of "slipping" along the shaft. Once that gets sloppy it allows the U-joint to orbit throwing the whole shaft out of whack. The bushing in the tailstock is just support, its not meant to keep the slip yoke perfectly aligned.

dynotech solved a vibraton problem that i had for several years.

Tough to say which part may have started things. But I've always painted parts. And for the past few years, I've painted the slip yoke shaft. I could see that the paint was wearing off on one side more than the other. This was when I first started taking the whole driveshaft / slip yoke assembly to the driveshaft shop for them to check things, as it didn't look correct. I pointed out my backyard observations. You know the rest of the story ("checks out fine")

But one thing is for sure,...the shaft was built out of round by over .020" and it's a thick wall steel unit. A different driveshaft guy said that there is no way to properly balance it and it's out enough to vibrate like crazy.

So I'm sure the slip yoke was causing some issues by not keeping things from getting off center,...but the biggest issue was the fact that the shaft was built wrong.

Glad to hear your problem is over Larry. How much did the new shaft cost?. It looks like they have pretty good customer service. Randy

Dynotech does do a great job.... I've been using them
for years..... never had a single problem with them.
Glad you got yours squared away

Hopefully you solved your problem., but when you say that the [paint ] you applied was wearing on one side of the yoke would lead me to believe that the out put shaft is slightly bent putting more pressure to one side of the yoke. If you haven't changed out the tail shaft bushing you should consider doing so.

Driveshaft was $395 plus tax....well worth it for new everything and aluminum. A real pleasure to talk to as well. After talking to two other driveshaft places, DynoTech was a pleasure. I'd tell each place that I've built a Dana 60 out of a truck case and re-used the yoke that was on there. Told them that it's a 1330 but has a big cap on it (1 1/8" not 1 1/16"). The other places seemed confused and had to do a lot of research to come up the the right ends / joints. I didn't feel real comfortable. I called DynoTech and the I tell the guy I have a yoke from a Ford Truck Dana 60, but it's not a typical 1330, and he interrupts me and says, "it's a Large Cap 1330, right?". The guy is reading my mind during our whole workup. I get a great DriveShaft. Excellent place!

It was wearing the same way with two different output shafts on my automatic transmissions with new output bushing and housings. AND with this new 833 4 speed. So 3 different transmissions with the same slip yoke wear (un even) Aint the transmission(s).

I just think that the driveshaft is heavier on one side (like a spinning banana) and it just took it's tool on everything before and after it.

I have a UPS pkg from DynoTech in the garage. Spoke with Steve on Monday and pkg arrived on Weds, very pleasant to deal with. Good to hear the positive feedback as I have not opened the box yet.

You will be ultra happy with that shaft from Dynotech. they did an MMC one for me that is trick and has been flawless. great vendor

DriveLine Services in Pittsburgh built a drive shaft for my belvedere. Put it in the car and the dash started to vibrate. Raced the car and the vibration was unbelivable. Had another company rebalance it and it seems to be better. Would not recomend them to anybody.

Glad you found your problem Larry. I've only used driveline service for a few small things, like my u-joint issue when I replaced the center section in my RoadRunner.

Hard to believe they are that bad. They've been there quite a long time.

This is encouraging information. I have had the same issue with my roadrunner since I've owned it (10 years). I've been through the car front to back plus new yoke, re-tubed driveshaft, multiple balancings, etc. Wayne Smothers has norrowed it down to the tube being slightly egg shaped, so a brand new drive shaft is the next step. Thanks for posting Larry.

Larry,
Is their phone # 800-633-5559? I've been chasing a driveline vibration in my truck for years.
Thanks,
Leigh

Larry, you actually Found the problem in your last thread! The new Diveshaft just confirms you were right with your original diagnosis. mike

Another happy Dynotech customer!

I will never have a DS done anywhere else